Malaysia Airlines MH17: Shooting down of aircraft will see US-Russia political chasm widen once more

Barack Obama has been in contact with world leaders since the disaster.

White House: Pete Souza

Barack Obama and Vladimir Putin were in the middle of a tense phone discussion on deteriorating US-Russia relations.

The conversation was not pleasant, described by an American aide as business-like, with "a candid exchange of views".

The Ukraine crisis had already pushed the Washington-Moscow relationship to its lowest point since the end of the Cold War.

Then it got a whole lot worse. The Russian president revealed some breaking news that had come to hand as the two leaders talked.

"I can confirm that President Putin near the end of this morning's phone call with President Obama noted the early reports of a downed passenger jet near the Russia-Ukraine border," White House spokesman Josh Earnest said.

Later, when speaking to reporters, Mr Obama was keen not to inflame an already tense impasse with Moscow.

"It looks like it may be a terrible tragedy, I've directed my national security team to stay in close contact with the Ukrainian government," he said during a brief visit to Delaware.

But there was no diplomatic velvet glove from vice president Joe Biden, who stated that the downing of the airliner was deliberate. He declared it was "blown out of the sky".

In Washington, Republican Party lawmakers who had been demanding a tough US response against Moscow from the Democrat president, called for even greater retaliation against Mr Putin if Russia was implicated in the crash.

"I believe there should be serious consequences if we find out that it was either Russian agents, Russian equipment or Russians directly that was responsible for the downing of this airliner," Republican senator Kelly Ayotte said.

Russia denies any involvement in the shoot-down, blaming Ukraine's government.

Mr Putin said the incident would not have happened if Kiev had not resumed its campaign against Russian separatists.

"This tragedy would not have happened if there had been peace on that land, or in any case if military operations in south-eastern Ukraine had not been renewed," he said.

Sanctions only served to stiffen Russian resolve

Just one day earlier, the United States had imposed a new raft of tougher sanctions against Moscow; punishment, Washington said, for Russia's support of pro-Moscow Ukraine separatists. Russia denies backing the rebels.

Rather than de-escalating the crisis, this economic and political broadside only served to stiffen Russian resolve.

The Washington Post noted that "Russians reacted with fury to the new US measures, with president Vladimir Putin telling journalists, in Brasilia, where he is visiting, that 'sanctions are driving Russian-American relations into a dead end'. In Moscow, deputy foreign minister Sergei Ryabkov vowed that Russia would take similar measures against the United States that would be 'quite painful and serious'."

The US measures were notably tougher than sanctions imposed by Washington's European allies who have greater economic ties with Moscow.

"It is highly likely that US national technical assets will be able to approximate the point of origin of the launch and the launcher.

"This means it will be up to the US to make the case as to who fired the missile, potentially putting Washington in a position of greater direct confrontation with Russia."

Striking similarities to downing of another civilian airliner

With Washington-Moscow relations now chilled to levels not seen since the end of the Cold War, there are some striking similarities with the downing of another civilian airliner that triggered one of the most dangerous low points of that 45-year super-power confrontation.

In 1983 a Soviet fighter plane shot down a Korean Air 747 which had strayed into sensitive Russian airspace west of Sakhalin Island in the Sea of Japan. All 269 passengers and crew aboard flight KAL007 were killed.

After initially denying knowledge of the incident, the Soviet Union first claimed the airliner was on a spying mission, and then accused the White House of deliberate provocation to test the readiness of Soviet air defences.

Thirty-one years on, the twisted wreckage of another airliner and the remains of 298 civilians lie strewn across the fields of Ukraine.

And as investigators search for the culprits and a motive, the US-Russia political chasm widens once more.